NIOSH logo and tagline

Immediately Dangerous To Life or Health (IDLH) Values

Print
Related Pages

Table of IDLH Values

Since the development of the original IDLH values in the 1970s and their subsequent revision in 1994 (NIOSH Documentation for Immediately Dangerous to Life or Health Concentrations (IDLH) (1994))pdf icon.  NIOSH has continued to review relevant scientific data and conduct research on methods for develop­ing IDLH values. This has led to the development of Current Intelligence Bulletin (CIB) 66: Derivation of Immediately Dangerous to Life or Health (IDLH) [NIOSH 2014-100].

It is the goal of NIOSH to re-evaluate all IDLH values included in the list below using the guidelines and criteria included in CIB 66. Until this occurs, this list contains IDLH values based on both the 1994 revised criteria and CIB 66 [NIOSH 2014-100]. It is important to note which criteria was applied to develop a specific IDLH value. When a chemical entry contains more than one IDLH value, the IDLH value based on CIB 66 should be treated as current NIOSH policy.

IDLH Values
Substance CAS no. IDLH Value (1994)* New/Updated Values
(2016-present)**
Acetaldehyde 75-07-0 2,000 ppm
Acetic acid 64-19-7 50 ppm
Acetic anhydride 108-24-7 200 ppm
Acetone 67-64-1 2,500 ppm
Acetonitrile 75-05-8 500 ppm 137 ppm (NIOSH Pub. No. 2017-203)
Acetylene tetrabromide 79-27-6 8 ppm
Acrolein 107-02-8 2 ppm
Acrylamide 79-06-1 60 mg/m3  
Acrylonitrile 107-13-1 85 ppm 60 ppm (NIOSH Pub. No. 2016-167)
Aldrin 309-00-2 25 mg/m3  
Allyl alcohol 107-18-6 20 ppm  
Allyl chloride 107-05-1 250 ppm  
Allyl glycidyl ether 106-92-3 50 ppm  
2 Aminopyridine 504-29-0 5 ppm  
Ammonia 7664-41-7 300 ppm  
Ammonium sulfamate 7773-06-0 1,500 mg/m3  
n-Amyl acetate 628-63-7 1,000 ppm  
sec-Amyl acetate 626-38-0 1,000 ppm  
Aniline 62-53-3 100 ppm  
o-Anisidine 90-04-0 50 mg/m3  
p-Anisidine 104-94-9 50 mg/m3  
Antimony compounds (as Sb) 7440-36-0 50 mg Sb/m3  
ANTU 86-88-4 100 mg/m3  
Arsenic (inorganic compounds, as As) 7440-38-2 (metal) 5 mg As/m3  
Arsine 7784-42-1 3 ppm  
Azinphosmethyl 86-50-0 10 mg/m3  
Barium (soluble compounds, as Ba) 7440-39-3 50 mg Ba/m3  
Benzene 71-43-2 500 ppm  
Benzonitrile 14 ppm (66 mg/m3) (NIOSH Pub. No. 2017-104)
Benzoyl peroxide 94-36-0 1,500 mg/m3  
Benzyl chloride 100-44-7 10 ppm  
Beryllium compounds (as Be) 7440-41-7 (metal) 4 mg Be/m3  
Boron oxide 1303-86-2 2,000 mg/m3  
Boron trifluoride 7637-07-2 25 ppm  
Bromine 7726-95-6 3 ppm  
Bromine Pentafluoride 1.7 ppm (NIOSH Pub. No. 2017-106)
Bromine trifluoride 7787-71-5 12 ppm (67 mg/m3) (NIOSH Pub. No. 2020-123)
Bromoform 75-25-2 850 ppm
Butane 106-97-8 1,600 ppm (>10% LEL) (NIOSH Pub. No. 2016-174)
1,3-Butadiene 106-99-0 2,000 ppm 2,000 ppm (10% LEL) (NIOSH Pub. No. 2017-107)
2-Butanone 78-93-3 3,000 ppm
2-Butoxyethanol 111-76-2 700 ppm
n-Butyl acetate 123-86-4 1,700 ppm
sec-Butyl acetate 105-46-4 1,700 ppm
tert-Butyl acetate 540-88-5 1,500 ppm
n-Butyl alcohol 71-36-3 1,400 ppm
sec-Butyl alcohol 78-92-2 2,000 ppm
tert-Butyl alcohol 75-65-0 1,600 ppm
n-Butylamine 109-73-9 300 ppm
tert-Butyl chromate 1189-85-1 15 mg Cr(VI)/m3
n-Butyl Acrylate 141-32-2 113 ppm (NIOSH Pub. No. 2016-173)
n-Butyl glycidyl ether 2426-08-6 250 ppm
n-Butyl mercaptan 109-79-5 500 ppm
p-tert-Butyltoluene 98-51-1 100 ppm  
Cadmium dust (as Cd) 7440-43-9 (metal) 9 mg Cd/m3  
Cadmium fume (as Cd) 1306-19-0 (CdO) 9 mg Cd/m3[Unc h]  
Calcium arsenate (as As) 7778-44-1 5 mg As/m3  
Calcium oxide 1305-78-8 25 mg/m3  
Camphor (synthetic) 76-22-2 200 mg/m3  
Carbaryl 63-25-2 100 mg/m3  
Carbon black 1333-86-4 1,750 mg/m3  
Carbon dioxide 124-38-9 40,000 ppm  
Carbon disulfide 75-15-0 500 ppm  
Carbon monoxide 630-08-0 1,200 ppm  
Carbon tetrachloride 56-23-5 200 ppm  
Chlordane 57-74-9 100 mg/m3  
Chlorinated camphene 8001-35-2 200 mg/m3  
Chlorinated diphenyl oxide n/a 5 mg/m3  
Chlorine 7782-50-5 10 ppm  
Chlorine dioxide 10049-04-4 5 ppm  
Chlorine Pentafluoride 13637-63-3 1.7 ppm (NIOSH Pub. No. 2016-170)
Chlorine Trifluoride 7790-91-2 12 ppm (45 mg/m3) (NIOSH Pub. No. 2020-124)
Chloroacetaldehyde 107-20-0 45 ppm
Chloroacetonitrile 107-14-2 14 ppm (NIOSH Pub. No. 2017-201)
alpha-Chloroacetophenone 532-27-4 15 mg/m3
Chlorobenzene 108-90-7 1,000 ppm
o-Chlorobenzylidene malononitrile 2698-41-1 2 mg/m3
Chlorobromomethane 74-97-5 2,000 ppm
Chlorodiphenyl (42% chlorine) 53469-21-9 5 mg/m3
Chlorodiphenyl (54% chlorine) 11097-69-1 5 mg/m3
Chloroform 67-66-3 500 ppm
1-Chloro-1-nitropropane 600-25-9 100 ppm
Chloroacetyl Chloride 79-04-9 1.3 ppm (6 mg/m3)(NIOSH Pub. No. 2016-169)
Chloropicrin 76-06-2 2 ppm
beta-Chloroprene 126-99-8 300 ppm
Chromic acid and chromates 1333-82-0 (CrO3) 15 mg Cr(VI)/m3
Chromium (II) compounds [as Cr(II)] n/a 250 mg Cr(II)/m3  
Chromium (III) compounds [as Cr(III)] n/a 25 mg Cr(III)/m3  
Chromium metal (as Cr) 7440-47-3 250 mg Cr/m3  
Coal tar pitch volatiles 65996-93-2 80 mg/m3  
Cobalt metal, dust and fume (as Co) 7440-48-4 20 mg Co/m3  
Copper (dusts and mists, as Cu) 7440-50-8 100 mg Cu/m3  
Copper fume (as Cu) 1317-38-0 (CuO) 100 mg Cu/m3  
Cotton dust (raw) n/a 100 mg/m3  
Crag (r) herbicide 136-78-7 500 mg/m3  
Cresol (o, m, p isomers) 95-48-7 250 ppm  
Crotonaldehyde 4170-30-3 50 ppm  
Cumene 98-82-8 900 ppm [10% LEL]  
Cyanides (as CN) n/a 25 mg/m3(as CN)  
Cyclohexane 110-82-7 1,300 ppm [10% LEL]  
Cyclohexanol 108-93-0 400 ppm  
Cyclohexanone 108-94-1 700 ppm  
Cyclohexene 110-83-8 2,000 ppm  
Cyclopentadiene 542-92-7 750 ppm  
2,4-D 94-75-7 100 mg/m3  
DDT 50-29-3 500 mg/m3  
Decaborane 17702-41-9 15 mg/m3  
Demeton 8065-48-3 10 mg/m3  
Diacetone alcohol 123-42-2 1,800 ppm [10% LEL]  
Diazomethane 334-88-3 2 ppm  
Diborane 19287-45-7 15 ppm  
Dibutyl phosphate 107-66-4 30 ppm  
Dibutyl phthalate 84-74-2 4,000 mg/m3  
o-Dichlorobenzene 95-50-1 200 ppm  
p-Dichlorobenzene 106-46-7 150 ppm  
Dichlorodifluoromethane 75-71-8 15,000 ppm  
1,3-Dichloro 5,5-dimethylhydantoin 118-52-5 5 mg/m3  
1,1-Dichloroethane 75-34-3 3,000 ppm  
1,2-Dichloroethylene 540-59-0 1,000 ppm  
Dichloroethyl ether 111-44-4 100 ppm  
Dichloromonofluoromethane 75-43-4 5,000 ppm  
1,1-Dichloro-1-Fluoroethane (HCFC-141b) 1717-00-6 1,700 ppm (8,245 mg/m3) (NIOSH Pub. No. 2016-168)
1,1-Dichloro 1-nitroethane 594-72-9 25 ppm
Dichlorotetrafluoroethane 76-14-2 15,000 ppm  
Dichlorvos 62-73-7 100 mg/m3  
Dieldrin 60-57-1 50 mg/m3  
Diethylamine 109-89-7 200 ppm  
2-Diethylaminoethanol 100-37-8 100 ppm  
Difluorodibromomethane 75-61-6 2,000 ppm  
Diglycidyl ether 2238-07-5 10 ppm  
Diisobutyl ketone 108-83-8 500 ppm  
Diisopropylamine 108-18-9 200 ppm  
Diketene 7.6 ppm(NIOSH Pub. No. 2017-108)
Dimethyl acetamide 127-19-5 300 ppm  
Dimethylamine 124-40-3 500 ppm  
N,N-Dimethylaniline 121-69-7 100 ppm  
Dimethyl 1,2-dibromo 2,2-dichlorethyl phosphate 300-76-5 200 mg/m3  
Dimethylformamide 68-12-2 500 ppm  
1,1-Dimethylhydrazine 57-14-7 15 ppm  
Dimethylphthalate 131-11-3 2,000 mg/m3  
Dimethyl sulfate 77-78-1 7 ppm  
Dinitrobenzene (o, m, p isomers) 528-29-0 50 mg/m3  
Dinitroocresol 534-52-1 5 mg/m3  
Dinitrotoluene 25321-14-6 50 mg/m3  
Di sec-octyl phthalate 117-81-7 5,000 mg/m3  
Dioxane 123-91-1 500 ppm  
Diphenyl 92-52-4 100 mg/m3  
Dipropylene glycol methyl ether 34590-94-8 600 ppm  
Endrin 72-20-8 2 mg/m3  
Epichlorohydrin 106-89-8 75 ppm  
EPN 2104-64-5 5 mg/m3  
Ethanolamine 141-43-5 30 ppm  
2-Ethoxyethanol 110-80-5 500 ppm  
2-Ethoxyethyl acetate 111-15-9 500 ppm  
Ethyl acetate 141-78-6 2,000 ppm [10% LEL]  
Ethyl acrylate 140-88-5 300 ppm  
Ethyl alcohol 64-17-5 3,300 ppm [10% LEL]  
Ethylamine 75-04-7 600 ppm  
Ethyl benzene 100-41-4 800 ppm [10% LEL]  
Ethyl bromide 74-96-4 2,000 ppm  
Ethyl butyl ketone 106-35-4 1,000 ppm  
Ethyl chloride 75-00-3 3,800 ppm [10% LEL]  
Ethylene chlorohydrin 107-07-3 7 ppm  
Ethylenediamine 107-15-3 1,000 ppm  
Ethylene Dibromide 106-93-4 46 ppm (354 mg/m3) (NIOSH Pub. No. 2020-125)
Ethylene dichloride 107-06-2 50 ppm  
Ethylene glycol dinitrate 628-96-6 75 mg/m3  
Ethyleneimine 151-56-4 100 ppm  
Ethylene oxide 75-21-8 800 ppm  
Ethyl ether 60-29-7 1,900 ppm [10% LEL]  
Ethyl formate 109-94-4 1,500 ppm  
Ethyl mercaptan 75-08-1 500 ppm  
N-Ethylmorpholine 100-74-3 100 ppm  
Ethyl silicate 78-10-4 700 ppm  
Ferbam 14484-64-1 800 mg/m3  
Ferrovanadium dust 12604-58-9 500 mg/m3  
Fluorides (as F) n/a 250 mg F/m3  
Fluorine 7782-41-4 25 ppm  
Fluorotrichloromethane 75-69-4 2,000 ppm  
Formaldehyde 50-00-0 20 ppm  
Formic acid 64-18-6 30 ppm  
Furan 110-00-9 13 ppm (35.1 mg/m3) (NIOSH Pub. No. 2016-171)
Furfural 98-01-1 100 ppm
Furfuryl alcohol 98-00-0 75 ppm
Glycidol 556-52-5 150 ppm
Graphite (natural) 7782-42-5 1,250 mg/m3
Hafnium compounds (as Hf) 7440-58-6 50 mg Hf/m3
Heptachlor 76-44-8 35 mg/m3
n-Heptane 142-82-5 750 ppm
Hexachloroethane 67-72-1 300 ppm
Hexachloronaphthalene 1335-87-1 2 mg/m3
Hexafluoroactone 684-16-2 9 ppm (61 mg/m3) (NIOSH Pub. No. 2016-172)
n-Hexane 110-54-3 1,100 ppm [10% LEL]  
2-Hexanone 591-78-6 1,600 ppm  
Hexone 108-10-1 500 ppm  
sec Hexyl acetate 108-84-9 500 ppm  
Hydrazine 302-01-2 50 ppm  
Hydrogen bromide 10035-10-6 30 ppm  
Hydrogen chloride 7647-01-0 50 ppm  
Hydrogen cyanide 74-90-8 50 ppm  
Hydrogen fluoride (as F) 7664-39-3 30 ppm  
Hydrogen peroxide 7722-84-1 75 ppm  
Hydrogen selenide (as Se) 7783-07-5 1 ppm  
Hydrogen sulfide 7783-06-4 100 ppm  
Hydroquinone 123-31-9 50 mg/m3  
Iodine 7553-56-2 2 ppm  
Iron oxide dust and fume (as Fe) 1309-37-1 2,500 mg Fe/m3  
Iron Pentacarbonyl 13463-40-6 0.4 ppm (NIOSH Pub. No. 2016-166)
Isoamyl acetate 123-92-2 1,000 ppm  
Isoamyl alcohol (primary and secondary) 123-51-3 500 ppm  
Isobutyl acetate 110-19-0 1,300 ppm [10% LEL]  
Isobutyl alcohol 78-83-1 1,600 ppm  
Isophorone 78-59-1 200 ppm  
Isopropyl acetate 108-21-4 1,800 ppm  
Isopropyl alcohol 67-63-0 2,000 ppm [10% LEL]  
Isopropylamine 75-31-0 750 ppm  
Isopropyl ether 108-20-3 1,400 ppm [10% LEL]  
Isopropyl glycidyl ether 4016-14-2 400 ppm  
Ketene 463-51-4 5 ppm  
Lead compounds (as Pb) 7439-92-1 100 mg Pb/m3  
Lindane 58-89-9 50 mg/m3  
Lithium hydride 7580-67-8 0.5 mg/m3  
L.P.G. 68476-85-7 2,000 ppm [10% LEL]  
Magnesium oxide fume 1309-48-4 750 mg/m3  
Malathion 121-75-5 250 mg/m3  
Maleic anhydride 108-31-6 10 mg/m3  
Manganese compounds (as Mn) 7439-96-5 (metal) 500 mg Mn/m3  
Mercury compounds [except (organo) alkyls, as Hg] 7439-97-6 (metal) 10 mg Hg/m3  
Mercury (organo) alkyl compounds(as Hg) n/a 2 mg Hg/m3  
Mesityl oxide 141-79-7 1,400 ppm [10% LEL]  
Methacrylonitrile 126-98-7 4.0 ppm (NIOSH Pub. No. 2017-204)
Methoxychlor 72-43-5 5,000 mg/m3  
Methyl acetate 79-20-9 3,100 ppm [10% LEL]  
Methyl acetylene 74-99-7 1,700 ppm [10% LEL]  
Methyl acetylenepropadiene mixture 59355-75-8 3,400 ppm [10% LEL]  
Methyl acrylate 96-33-3 250 ppm  
Methylal 109-87-5 2,200 ppm [10% LEL]  
Methyl alcohol 67-56-1 6,000 ppm  
Methylamine 74-89-5 100 ppm  
Methyl (namyl) ketone 110-43-0 800 ppm  
Methyl bromide 74-83-9 250 ppm  
Methyl Cellosolve (r) 109-86-4 200 ppm  
Methyl Cellosolve (r) acetate 110-49-6 200 ppm  
Methyl chloride 74-87-3 2,000 ppm  
Methyl chloroform 71-55-6 700 ppm  
Methylcyclohexane 108-87-2 1,200 ppm [10% LEL]  
Methylcyclohexanol 25639-42-3 500 ppm  
o-Methylcyclohexanone 583-60-8 600 ppm  
Methylene bisphenyl isocyanate 101-68-8 75 mg/m3  
Methylene chloride 75-09-2 2,300 ppm  
Methyl formate 107-31-3 4,500 ppm  
5-Methyl 3-heptanone 541-85-5 100 ppm  
Methyl hydrazine 60-34-4 20 ppm  
Methyl iodide 74-88-4 100 ppm  
Methyl isobutyl carbinol 108-11-2 400 ppm  
Methyl isocyanate 624-83-9 3 ppm 0.12 ppm (0.28 mg/m3) (NIOSH Pub. No. 2017-105)
Methyl mercaptan 74-93-1 150 ppm  
Methyl methacrylate 80-62-6 1,000 ppm  
Methyl styrene 98-83-9 700 ppm  
Mica 12001-26-2 1,500 mg/m3  
Molybdenum (insoluble compounds, as Mo) n/a 5,000 mg Mo/m3  
Molybdenum (soluble compounds, as Mo) n/a 1,000 mg Mo/m3  
Monomethyl aniline 100-61-8 100 ppm  
Morpholine 110-91-8 1,400 ppm [10% LEL]  
Naphtha (coal tar) 8030-30-6 1,000 ppm [10% LEL]  
Naphthalene 91-20-3 250 ppm  
Nickel carbonyl (as Ni) 13463-39-3 2 ppm  
Nickel metal and other compounds (as Ni) 7440-02-0 (Metal) 10 mg Ni/m3  
Nicotine 54-11-5 5 mg/m3  
Nitric acid 7697-37-2 25 ppm  
Nitric oxide 10102-43-9 100 ppm  
p-Nitroaniline 100-01-6 300 mg/m3  
Nitrobenzene 98-95-3 200 ppm  
p-Nitrochlorobenzene 100-00-5 100 mg/m3  
Nitroethane 79-24-3 1,000 ppm  
Nitrogen dioxide 10102-44-0 20 ppm 13 ppm (NIOSHPub. No. 2017-202)
Nitrogen trifluoride 7783-54-2 1,000 ppm  
Nitroglycerine 55-63-0 75 mg/m3  
Nitromethane 75-52-5 750 ppm  
1-Nitropropane 108-03-2 1,000 ppm  
2-Nitropropane 79-46-9 100 ppm  
Nitrotoluene (o, m, p isomers) 88-72-2 200 ppm  
Octachloronaphthalene 2234-13-1 Unknown  
Octane 111-65-9 1,000 ppm [10% LEL]  
Oil mist (mineral) 8012-95-1 2,500 mg/m3  
Osmium tetroxide (as Os) 20816-12-0 1 mg Os/m3  
Oxalic acid 144-62-7 500 mg/m3  
Oxygen difluoride 7783-41-7 0.5 ppm  
Ozone 10028-15-6 5 ppm  
Paraquat 1910-42-5 1 mg/m3  
Parathion 56-38-2 10 mg/m3  
Pentaborane 19624-22-7 1 ppm  
Pentachloronaphthalene 1321-64-8 Unknown  
Pentachlorophenol 87-86-5 2.5 mg/m3  
n-Pentane 109-66-0 1,500 ppm [10% LEL]  
2-Pentanone 107-87-9 1,500 ppm  
Perchloromethyl mercaptan 594-42-3 10 ppm  
Perchloryl fluoride 7616-94-6 100 ppm  
Petroleum distillates (naphtha) 8002-05-9 1,100 ppm [10% LEL]  
Phenol 108-95-2 250 ppm  
p-Phenylene diamine 106-50-3 25 mg/m3  
Phenyl ether (vapor) 101-84-8 100 ppm  
Phenyl etherbiphenyl mixture (vapor) 8004-13-5 10 ppm  
Phenyl glycidyl ether 122-60-1 100 ppm  
Phenylhydrazine 100-63-0 15 ppm  
Phosdrin 7786-34-7 4 ppm  
Phosgene 75-44-5 2 ppm  
Phosphine 7803-51-2 50 ppm  
Phosphoric acid 7664-38-2 1,000 mg/m3  
Phosphorus (yellow) 7723-14-0 5 mg/m3  
Phosphorus pentachloride 10026-13-8 70 mg/m3  
Phosphorus pentasulfide 1314-80-3 250 mg/m3  
Phosphorus trichloride 7719-12-2 25 ppm  
Phthalic anhydride 85-44-9 60 mg/m3  
Picric acid 88-89-1 75 mg/m3  
Pindone 83-26-1 100 mg/m3  
Platinum (soluble salts, as Pt) n/a 4 mg Pt/m3  
Portland cement 65997-15-1 5,000 mg/m3  
Propane 74-98-6 2,100 ppm [10% LEL]  
n-Propyl acetate 109-60-4 1,700 ppm  
n-Propyl alcohol 71-23-8 800 ppm  
Propylene dichloride 78-87-5 400 ppm  
Propylene imine 75-55-8 100 ppm  
Propylene oxide 75-56-9 400 ppm  
n-Propyl nitrate 627-13-4 500 ppm  
Pyrethrum 8003-34-7 5,000 mg/m3  
Pyridine 110-86-1 1,000 ppm  
Quinone 106-51-4 100 mg/m3  
Rhodium (metal fume and insoluble compounds, as Rh) 7440-16-6 (metal) 100 mg Rh/m3  
Rhodium (soluble compounds, as Rh) n/a 2 mg Rh/m3  
Ronnel 299-84-3 300 mg/m3  
Rotenone 83-79-4 2,500 mg/m3  
Selenium compounds (as Se) 7782-49-2 1 mg Se/m3  
Selenium hexafluoride 7783-79-1 2 ppm  
Silica, amorphous 7631-86-9 3,000 mg/m3  
Silica, crystalline (respirable dust) 14808-60-7  
cristobalite/tridymite 14808-60-7 25 mg/m3  
quartz/tripoli 14808-60-7 50 mg/m3  
Silver (metal dust and soluble compounds, as Ag) 7440-22-4 (metal) 10 mg Ag/m3  
Soapstone n/a 3,000 mg/m3  
Sodium fluoroacetate 62-74-8 2.5 mg/m3  
Sodium hydroxide 1310-73-2 10 mg/m3  
Stibine 7803-52-3 5 ppm  
Stoddard solvent 8052-41-3 20,000 mg/m3  
Strychnine 57-24-9 3 mg/m3  
Styrene 100-42-5 700 ppm  
Sulfur dioxide 7446-09-5 100 ppm  
Sulfuric acid 7664-93-9 15 mg/m3  
Sulfur monochloride 10025-67-9 5 ppm  
Sulfur pentafluoride 5714-22-7 1 ppm  
Sulfuryl fluoride 2699-79-8 200 ppm  
2,4,5-T 93-76-5 250 mg/m3  
Talc 14807-96-6 1,000 mg/m3  
Tantalum (metal and oxide dust, as Ta) 7440-25-7 (metal) 2,500 mg Ta/m3  
TEDP 3689-24-5 10 mg/m3  
Tellurium compounds (as Te) 13494-80-9 25 mg Te/m3  
Tellurium hexafluoride 7783-80-4 1 ppm  
TEPP 107-49-3 5 mg/m3  
Terphenyl (o, m, p isomers) 84-15-1 500 mg/m3  
1,1,1,2-Tetrachloro 2,2-difluoroethane 76-11-9 2,000 ppm  
1,1,2,2-Tetrachloro 1,2-difluoroethane 76-12-0 2,000 ppm  
1,1,2,2-Tetrachloroethane 79-34-5 100 ppm  
Tetrachloroethylene 127-18-4 150 ppm  
Tetrachloronaphthalene 1335-88-2 Unknown  
Tetraethyl lead (as Pb) 78-00-2 40 mg Pb/m3  
Tetrahydrofuran 109-99-9 2,000 ppm [10% LEL]  
Tetramethyl lead (as Pb) 75-74-1 40 mg Pb/m3  
Tetramethyl succinonitrile 3333-52-6 5 ppm  
Tetranitromethane 509-14-8 4 ppm  
Tetryl 479-45-8 750 mg/m3  
Thallium (soluble compounds, as Tl) n/a 15 mg Tl/m3  
Thiram 137-26-8 100 mg/m3  
Tin (inorganic compounds, as Sn) n/a 100 mg Sn/m3  
Tin (organic compounds, as Sn) n/a 25 mg Sn/m3  
Titanium dioxide 13463-67-7 5,000 mg/m3  
Toluene 108-88-3 500 ppm  
Toluene 2,4-diisocyanate 584-84-9 2.5 ppm  
o-Toluidine 95-53-4 50 ppm  
Tributyl phosphate 126-73-8 30 ppm  
1,1,2-Trichloroethane 79-00-5 100 ppm  
Trichloroethylene 79-01-6 1,000 ppm  
Trichloronaphthalene 1321-65-9 Unknown  
1,2,3-Trichloropropane 96-18-4 100 ppm  
1,1,2-Trichloro 1,2,2-trifluoroethane 76-13-1 2,000 ppm  
Triethylamine 121-44-8 200 ppm  
Trifluorobromomethane 75-63-8 40,000 ppm  
2,4,6-Trinitrotoluene 118-96-7 500 mg/m3  
Triorthocresyl phosphate 78-30-8 40 mg/m3  
Triphenyl phosphate 115-86-6 1,000 mg/m3  
Turpentine 8006-64-2 800 ppm  
Uranium (insoluble compounds, as U) 7440-61-1 (metal) 10 mg U/m3  
Uranium (soluble compounds, as U) n/a 10 mg U/m3  
Vanadium dust 1314-62-1 35 mg V/m3  
Vanadium fume 1314-62-1 35 mg V/m3  
Vinyl toluene 25013-15-4 (inhibited) 400 ppm  
Warfarin 81-81-2 100 mg/m3  
Xylene (o, m, p isomers) 95-47-6 900 ppm  
Xylidine 1300-73-8 50 ppm  
Yttrium compounds (as Y) 7440-65-5 500 mg Y/m3  
Zinc chloride fume 7646-85-7 50 mg/m3  
Zinc oxide 1314-13-2 500 mg/m3  
Zirconium compounds (as Zr) 7440-67-7 (Metal) 25 mg Zr/m3